This application is related to the subject matter of copending U.S. application Ser. No. 813,191 which was filed on July 5, 1977 and copending U.S. application Ser. No. 828,563 which was filed on Aug. 29, 1977; both said copending applications have been assigned to the assignee of the present application.
This invention relates to an apparatus and method for accurately controlling the velocity of a moving member, like a print head carrier, for example, which moves along the platen of a printer, and for providing timing signals for printing uniformly spaced dots when using a wire matrix printer as the printing element, even with some variation in the velocity of the print head carrier.
Most systems of the prior art utilize a tachometer which is coupled to the drive shaft of the motor driving the print head carrier, and the tachometer is used to feed back an analog signal which is proportional to the speed of the motor. The analog signal is then compared with a reference signal in a comparator means which controls the operating speed of the motor by a variety of techniques disclosed in the prior art.